Wriggling Monsters sounds like a great name for it to me!
Mine was worst during pregnancies and then after I had my youngest. It was all over my body and when I lay in bed feeding him (we co-slept) I would end up crying because keeping still was so unbearable. With my older children I slept and nursed them through the night, sometimes would wake up and not even remember having fed them, but last time round I was lying awake half the night feeling like I was being tortured.
It is much better since I went gluten free but I still get it sometimes. I find it is worst is my feet and hands are hot, if I eat sugary food in the evening and I get hot, puffy hands and feet and restless legs, so I try to avoid that. Mine's not caused by iron deficiency, my Hb is always good.
My dad used to get it too, he called it "jumping leg", we used to sit watching Morse together and he'd keep thumping his leg on the floor. We kids used to laugh about it but now I know it is definately NOT funny! My dad didn't have HMS but his mum had many of the symptoms (her "rheumatics" etc) so I think the gene came via him.
HMS (diagnosed Feb 2012, aged 38): food intolerances incl gluten, allergies, asthma, IBS, GERD, RLS, hypoglycaemia
"Feelings come and go like clouds in a windy sky. Conscious breathing is my anchor." Thich Nhat Hanh